Gridded 1/24-degree daily climate for the western United States, 1951–2025

This dataset contains daily grids of climate for the 75-year period from January 1 1951 to December 31 2025 at a geographic resolution of 1/24° (~4 km) across the western US domain, defined as the 11 westernmost states in the coterminous US (Arizona, California, Colorado, Idaho, Montana, New Mexico, Nevada, Oregon, Utah, Washington, and Wyoming). Climate variables represented are precipitation total (prec, mm), daily maximum temperature (tmax, °C), daily minimum temperature (tmin, °C), mean vapor pressure (ea, hPa), mean wind velocity two meters above the surface (wind, m s-1), mean downward solar radiation at the surface (solar, W m-2), mean downward longwave radiation at the surface (longwave, W m-2), and surface pressure (psfc, hPa). The dataset was produced in order to make possible long simulations of western US environmental processes such as hydrology, wildfire, and ecosystem dynamics. The dataset was produced by combining data from a variety of publicly available sources, prioritizing station-based observational datasets (as opposed to reanalysis datasets) when possible. This the methods used to produce this dataset will be described in an upcoming publication and a link to that publication will be added to the dataset's metadata at that time. Data sources for each variable: prec, tmax, and tmin: nClimGrid-Daily: https://www.ncei.noaa.gov/products/land-based-station/nclimgrid-daily ea: from PRISM daily 4-km dewpoint from 1980–end: https://prism.oregonstate.edu/ ea: from Rahimi et al. (2024) WUS-D3 9-km dynamically downscaled ERA5 daily specific humidity and vapor pressure and then calibrated using quantile mapping to match monthly climatologies of daily distributions of PRISM-derived ea during 1981–2020. https://wrf-cmip6-noversioning.s3.amazonaws.com/index.html#downscaled_products/reanalysis/era5/postprocess/d02/ wind: WTK-LED 4-km dynamically-downscaled ERA5 wind reanalysis for 2001–2020: https://doi.org/10.25984/2504176 wind: from Rahimi et al. (2024) WUS-D3 9-km dynamically downscaled ERA5 for 1951–2000 and 2021–March 2025, calibrated to WTI-LED winds using quantile mapping to match monthly climatologies of daily distributions during 2001–2020.wind: from GridMET for April 2025–end, calibrated to WTI-LED winds using quantile mapping to match monthly climatologies of daily distributions during 2001–2020: https://www.climatologylab.org/gridmet.html solar: from PRISM daily 4-km downward solar radiation incident on the sloped surface from 1980–end. solar: from Rahimi et al. (2024) WUS-D3 9-km dynamically downscaled ERA5 for 1951–1979, calibrated using quantile mapping to match monthly climatologies of daily distributions of PRISM-derived solar during 1981–2020. longwave: from Rahimi et al. (2024) WUS-D3 9-km dynamically downscaled ERA5 for 1951–March 2025. longwave: extended from April 2025–end with NLDAS2, calibrated using quantile mapping to match monthly climatologies of daily distributions of the dynamically downscaled ERA5 data during 1981–2020: https://hydro1.gesdisc.eosdis.nasa.gov/data/NLDAS/NLDAS_FORA0125_H.2.0/ ps: from Rahimi et al. (2024) WUS-D3 9-km dynamically downscaled ERA5 for 1951–March 2025. 9-km gridded data downscaled to 4-km with bilinear interpolation and then each 4-km grid’s dataset was multiplicatively adjusted so that 1981–2020 means matched the long-term mean surface pressure (pmean; hPa) expected from 4-km gridded mean elevation (in m above sea level pmean = 1013.25 * (1 - (2.2557*10^-5) * elev).^5.25588. ps: extended from April 2025–end with NLDAS2, calibrated using quantile mapping to match monthly climatologies of daily distributions of the dynamically downscaled ERA5 data during 1981–2020. References nClimGrid-Daily: Durre, I., Arguez, A., Schreck III, C. J., Squires, M. F., and Vose, R. S.: Daily high-resolution temperature and precipitation fields for the contiguous United States from 1951 to present, Journal of Atmospheric and Oceanic Technology, 39, 1837–1855, https://doi.org/10.1175/JTECH-D-22-0024.1, 2022. GridMET Abatzoglou, J. T.: Development of gridded surface meteorological data for ecological applications and modelling, Int J Climatol, 33, 121–131, https://doi.org/10.1002/joc.3413, 2013. PRISM Daly, C., Doggett, M. K., Smith, J. I., Olson, K. V., Halbleib, M. D., Dimcovic, Z., Keon, D., Loiselle, R. A., Steinberg, B., and Ryan, A. D.: Challenges in observation-based mapping of daily precipitation across the conterminous United States, Journal of Atmospheric and Oceanic Technology, 38, 1979–1992, https://doi.org/10.1175/JTECH-D-21-0054.1, 2021. Rupp, D. E., Daly, C., Doggett, M. K., Smith, J. I., and Steinberg, B.: Mapping an observation-based global solar irradiance climatology across the conterminous United States, Journal of Applied Meteorology and Climatology, 61, 857–876, https://doi.org/10.1175/JAMC-D-21-0236.1, 2022. WUS-D3 9-km dynamically downscaled ERA5 reanalysis Rahimi, S., Huang, L., Norris, J., Hall, A., Goldenson, N., Krantz, W., Bass, B., Thackeray, C., Lin, H., and Chen, D.: An overview of the Western United States Dynamically Downscaled Dataset (WUS-D3), Geoscientific Model Development, 17, 2265–2286, https://doi.org/10.5194/gmd-17-2265-2024, 2024. WTK-LED wind reanalysis Draxl, C., Wang, J., Sheridan, L., Jung, C., Bodini, N., Buckhold, S., Aghili, C. T., Peco, K., Kotamarthi, R., Kumler, A., Phillips, C., Purkayastha, A., Young, E., Rosenlieb, E., and Heidi, T.: WTK-LED: The wind toolkit long-term ensemble dataset, National Renewable Energy Laboratory (NREL), Golden, CO, https://doi.org/10.2172/2473210, 2024. NLDAS2 Xia, Y., Mitchell, K., Ek, M., Sheffield, J., Cosgrove, B., Wood, E., Luo, L., Alonge, C., Wei, H., Meng, J., Linvneh, B., Lettenmaier, D., Koren, V., Duan, Q., Mo, K., Fan, Y., and Mocko, D.: Continental-scale water and energy flux analysis and validation for the North American Land Data Assimilation System project phase 2 (NLDAS-2): 1. Intercomparison and application of model products, J Geophys Res-Atmos, 117, D03109, https://doi.org/10.1029/2011JD016051, 2012.